Conventional industrial clothes dryers consist of a cylindrical drum rotatably Dowered along a horizontal axle. The drum is perforated, and is adapted to support a load of damp clothing. Warm dry air flows transversely through the bores of the perforated drum, to air dry the clothing.
A problem associated with such industrial drums, particularly those used in hospitals for cleaning clothes of medical personnel, pertains to the fabric lint, general linen, and the plastic material from these clothes during their drying inside the drum: the plastic material in particular tends under static electricity forces and also centrifugal forces to adhere to the interior wall of the drum. Because the drum interior wall is hot, due to mainly convective, but also to some extent conductive and radiative heat transfer forces, heat fusion of the plastic material occurs against the drum interior wall, thus eventually clogging the bores of the perforated drum. Unclogging the rotating drum bores by removing the melted or fused plastic material adhered to the drum interior wall is a relatively lengthy operation, which means that the industrial dryer unit does not operate during that time. This downtime, which occurs relatively frequently, reduces the efficiency of operations of industrial dryer units, and thus increases labour costs.